Is RA27/3 rubella immunization a cause of chronic fatigue?

Electrolytes as predictors of fibro fatigue scores in Long-COVID patients

BACKGROUND

The complex effects of Long-COVID, a syndrome marked by enduring symptoms after COVID-19 infection, with an emphasis on patients' differing degrees of fibro fatigue (FF). Electrolyte disturbances may affect the severity of FF and may be used as a predictive tool for severe FF in Long-COVID patients.

OBJECTIVE

The aim is to use the electrolyte levels for prediction of the Long-COVID patients with high FF levels.

METHODS

The electrolyte levels, calcium, and magnesium, as well as albumin and C-reactive protein levels were measured in 120 Long-COVID patients and 60 controls. FF scale was used for scoring the fatigue severity in all subjects. Patients were divided into high-FF (FF score>25) and moderate-FF group (FF score<25).

RESULTS

FF is the major effector on the serum biomarker levels. High-FF group had older people, longer disease durations, lower SpO2, higher CRP, and higher peak temperatures than the control group. High-FF group has a significant decrease in serum total and ionized calcium compared with the controls and low-FF group. After controlling the cofounders, the major factor controlling the levels of the measured biomarkers is the FF value (Partial η2 = 0.468). The ROC-AUC analysis showed that the peak body temperature, Low-SpO2, high-CRP, and low electrolytes can predict the high-FF in a patient with Long-COVID with a moderate sensitivity and specificities (61.6-70%).

CONCLUSION

Long-COVID patients have an elevation in FF score. The decline in electrolytes can predict the severity of FF with moderate sensitivities and specificities.

Pain associated with COVID-19 vaccination is unrelated to skin biopsy abnormalities

Introduction

Previous clinical observations raised the possibility that COVID-19 vaccination might trigger a small-fibre neuropathy.

Objectives

In this uncontrolled observational study, we aimed to identify small fibre damage in patients complaining of generalized sensory symptoms and pain after COVID-19 vaccination.

Methods

We collected clinical data, including a questionnaire for assessing autonomic symptoms (Composite Autonomic Symptom Score-31), and investigated quantitative sensory testing (QST) and skin biopsy in 15 prospectively enrolled patients with generalized sensory symptoms and pain after COVID-19 vaccination. Nine patients complaining of orthostatic intolerance also underwent cardiovascular autonomic tests.

Results

We found that all patients experienced widespread pain, and most of them (11 of 15) had a fibromyalgia syndrome. All patients had normal skin biopsy findings, and in the 9 patients with orthostatic intolerance, cardiovascular autonomic tests showed normal findings. Nevertheless, 5 patients had cold and warm detection abnormalities at the QST investigation.

Conclusions

In our study, most patients complaining of generalized sensory symptoms and pain after COVID-19 vaccination had clinical and diagnostic test findings compatible with a fibromyalgia syndrome. Although the abnormal QST findings we found in 5 patients might be compatible with a small-fibre neuropathy, they should be cautiously interpreted given the psychophysical characteristics of this diagnostic test. Further larger controlled studies are needed to define precisely the association between small fibre damage and COVID-19 vaccination.

Neuroinflammation and Cytokines in Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS): A Critical Review of Research Methods

Myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) is the label given to a syndrome that can include long-term flu-like symptoms, profound fatigue, trouble concentrating, and autonomic problems, all of which worsen after exertion. It is unclear how many individuals with this diagnosis are suffering from the same condition or have the same underlying pathophysiology, and the discovery of biomarkers would be clarifying. The name "myalgic encephalomyelitis" essentially means "muscle pain related to central nervous system inflammation" and many efforts to find diagnostic biomarkers have focused on one or more aspects of neuroinflammation, from periphery to brain. As the field uncovers the relationship between the symptoms of this condition and neuroinflammation, attention must be paid to the biological mechanisms of neuroinflammation and issues with its potential measurement. The current review focuses on three methods used to study putative neuroinflammation in ME/CFS: (1) positron emission tomography (PET) neuroimaging using translocator protein (TSPO) binding radioligand (2) magnetic resonance spectroscopy (MRS) neuroimaging and (3) assays of cytokines circulating in blood and cerebrospinal fluid. PET scanning using TSPO-binding radioligand is a promising option for studies of neuroinflammation. However, methodological difficulties that exist both in this particular technique and across the ME/CFS neuroimaging literature must be addressed for any results to be interpretable. We argue that the vast majority of ME/CFS neuroimaging has failed to use optimal techniques for studying brainstem, despite its probable centrality to any neuroinflammatory causes or autonomic effects. MRS is discussed as a less informative but more widely available, less invasive, and less expensive option for imaging neuroinflammation, and existing studies using MRS neuroimaging are reviewed. Studies seeking to find a peripheral circulating cytokine "profile" for ME/CFS are reviewed, with attention paid to the biological and methodological reasons for lack of replication among these studies. We argue that both the biological mechanisms of cytokines and the innumerable sources of potential variance in their measurement make it unlikely that a consistent and replicable diagnostic cytokine profile will ever be discovered.

Neuroendocrine and immune aspects of fibromyalgia

Fibromyalgia is a form of non-articular rheumatism characterised by long term (>3 months) and widespread musculoskeletal aching, stiffness and pressure hyperalgesia at characteristic soft tissue sites, called soft tissue tender points. The biophysiology of fibromyalgia, however, has remained elusive and the treatment remains mainly empirical. This article reviews the neuroendocrine-immune pathophysiology of fibromyalgia. There is no major evidence that fibromyalgia is accompanied by activation of the inflammatory response system, by immune activation or by an inflammatory process. There is some evidence that fibromyalgia is accompanied by some signs of immunosuppression, suggesting that immunomodifying drugs could have potential in the treatment of fibromyalgia. Recent trials with cytokines, such as interferon-alpha, have been undertaken in patients with fibromyalgia. Immunotherapy with these agents, however, may induce symptoms reminiscent of fibromyalgia and depression in a considerable number of patients. Lowered serum activity of prolyl endopeptidase (PEP), a cytosolic endopeptidase that cleaves peptide bonds on the carboxyl side of proline in proteins of relatively small molecular mass, may play a role in the biophysiology of fibromyalgia through diminished inactivation of algesic and depression-related peptides, e.g. substance P. Trials with PEP agonists could be worthwhile in fibromyalgia. The muscle energy depletion hypothesis of fibromyalgia is supported by findings that this condition is accompanied by lowered plasma levels of branched chain amino acids (BCAAs), i.e. valine, leucine and isoleucine. Since there is evidence that BCAA supplementation decreases muscle catabolism and has ergogenic values, a supplemental trial with BCAAs in fibromyalgia appears to be justified.

Randomised double-blind placebo-controlled study on adverse effects of rubella immunisation in seronegative women

BACKGROUND

The objective of our study was to investigate the association of adverse clinical musculoskeletal and neurological events in healthy postpartum women with live attenuated (RA27/3 strain) rubella-virus vaccine, and to assess the frequency of acute and recurrent arthralgia and arthritis and associations with acute and recurrent muscle pain (myalgia) and neurological manifestations (paraesthesias).

METHODS

We used a randomised placebo-controlled, double-blind design in a community setting. 636 women were enrolled and, after 90 women dropped out, 546 healthy women aged 18-41 years, who were rubella seronegative on routine screening were immunised parenterally with either monovalent live attenuated (RA27/3 strain) rubella vaccine (n = 270) or saline placebo (n = 276) in the postpartum period. Outcome measures were the occurrence of acute and persistent or recurrent joint manifestations (arthralgia or arthritis) at 1, 3, 6, 9, and 12 months after immunisation. Occurrence of muscle pain (myalgia), and neurological symptoms (paraesthesia) was also assessed at the same times.

FINDINGS

543 women completed 1-month follow-up. 456 women completed the 12-month assessment. There were no differences at the time of immunisation between rubella vaccine and placebo groups in distribution of age, ethnic origin, parity, time between delivery and immunisation, breastfeeding history, or histories of earlier rubella vaccination or joint complaints. Results indicated a significantly higher incidence (p = 0.006; odds ratio = 1.73 [95% CI = 1.17-2.57]) of acute joint manifestations in rubella-vaccine recipients (30%) than in placebo recipients (20%). Frequency of chronic (recurrent) arthralgia or arthritis was only marginally significant (p = 0.042; 1.58 [1.01-2.45]).

INTERPRETATION

RA27/3 rubella vaccine given to seronegative women during the postpartum period was significantly associated with development of acute arthralgia or arthritis. Although the numbers of women assessed and length of follow-up revealed only marginally significant differences in persistent or recurrent joint manifestations between rubella vaccine and placebo recipients, it is possible that susceptible women who are given rubella vaccination may experience this outcome.

Altered interleukin-2 secretion in patients with primary fibromyalgia syndrome

Interleukin-2 (IL-2) production was studied in T lymphocytes and isolated CD4+ T lymphocytes from 12 patients with primary fibromyalgia syndrome and 10 healthy volunteers. The dose and time kinetics of IL-2 production by concanavalin A-stimulated T cells and CD4+ T cells of fibromyalgia patients differed from findings in controls by 1) a need for a higher concentration of mitogen in order to achieve optimal IL-2 secretion, and 2) a delay in the peak time of optimal IL-2 secretion. Unlike normal IL-2 secretion, which was higher after removal of CD8+ T cells, the pattern and degree of IL-2 secretion by cells from fibromyalgia patients were not changed following removal of CD8+ T cells. Addition of calcium ionophore in assays using suboptimal concanavalin A concentrations did not correct the reduction in IL-2 secretion by fibromyalgia patient T cells, but addition of phorbol myristate acetate induced normal secretion of IL-2. These findings suggest that there is a defect in the IL-2 pathway, which is related to protein kinase C activation and does not involve impairment of Ca2+ elevation, in patients with fibromyalgia.

Left-right spatial agnosia and other mental defects that characterize clinical researchers

There are mathematical rules for determining the logical significance of data, just as there are such rules for determining the statistical significance of data. Logical significance reflects the question a study is asking, whereas statistical significance reflects how well it has been answered. Clinical researchers routinely make an incorrect determination as to their study's logical significance because of a spatial (left-right) agnosia. More diffuse cognitive dysfunctions are encouraged by journals that expect clinicians to report on a study as a prerequisite for communicating their pre-existing opinions. The unwillingness or inability of the clinical community to acknowledge this problem reflects a related anosagnosia.